Method of making round compound metallic articles



Oct. 24, 1939.

H. mm 2,111,435

HETHOD OF MAKING ROUND COMPOUND METALLIC ARTICLES Filed Oct. 14, 1935lIi ' mi s/mm HTTaR EV H0715 lfreiz Patented Oct. 24, 1939 METHOD OFMAKING ROUND COIVIPOUND METALLIC ARTICLES Hans Kretz, Pforzheim,Germany, assignor to Fr. Kammerer A.-G., Pforzheim, Germany, a

corporation of Germany Application October 14, 1936, Serial No. 105,604

- In Germany October 22, 1935 2 Claims.

My invention relates to a method of making round compound metallicarticles which may be tubular or solid..

It is an object of my invention to provide a 5 method by which bettercompound articles are wire. 5 obtained than could be made heretofore.Referring now to the drawing, and first to To this end, I place a sheathof welding metal Fig. 1, this machine for making tubular comon thearticle-which may be a tube or a solid pound articles is equipped with aset comprisbody, e. g., wire, heat the article and the sheath ing two rmore r dially ctin pid be n 0 on the article to welding heat, shift bothmemreciprocating dies, or percussion jaws hi and he. bers axially whilestriking blows in radial dibetween which a tubular article a and asheath rection, and in rapid succession, against the p aced to on amandrel are Pressed sheath, and effect relative rotation of the pointsor drawn at. welding temperature in the direcwhere the blows are struckagainst the sheath tion of the arrow 2'. The size and movement of .6 andthe article, preferably by suitable reciprothe percussion jaws are suchthat ,in closed pocating dies, or percussion jaws, about the axis sitionthey leave a passage similar'to a drawing of the article. I may rotateeither the article channel in a drawing-die, so that the crosswithrespect to the reciprocating dies, or persectional area of the tube issufiiciently reduced. cussion paws, or, conversely, I may rotate the Toensure that the tube is workd on all points :0 dies with respect to thearticle. of its periphery, the percussion jaws circulate 20 It isanother object of my invention to prosufllciently quickly about thetubeduring their vide a method, as specified, for the manufacture beatingmovement. of tubular compound articles. It is likewise possible for thetube to carry To this end, I place the tubular article on a out asufflciently rapid rotary movement about :5 mandrel with which it isshifted axially, and its axis besides its feeding movement, in whichotherwise proceed as described above. case the percussion jaws donotcirculate.

I am aware that it is old in this art to make Referring now to Fig. 2,when producing comcompound tubes by welding a sheath on a tupound wiresa solid wire 70 (Fig. 4), takes the bular article, but in this oldmethod the weldplace of the inner tube a so that it is not neceso ingpressure is exerted by rolls, and not by resary to employ a membercorresponding to the ciprocating dies, or percussion jaws, as in mymandrel c. In other respects the method remains invention. It has beenfound that with rolls it unchanged. is impossible to exert uniformwelding pressure I claim: all over the sheath, and so the weld is notperfect. 1. The method of welding round compound 5 I am also aware thatdies, or percussion jaws, metallic articles of great length, comprisingplacare old in the art of making plain tubes, and ing a sheath ofwelding metal on the article, my invention does not reside in the use ofdies, heating the article and the sheath thereon to nor in the heatingof the article and its sheath welding heat, shifting both membersaxially and but it resides in the combination of certain feawhile stillheated striking blows in radial ditures which maybe old individually buthave rection, and in rapid succession, against the never been combinedbefore. sheath, and effecting relative rotation of the My newcombination is very useful since the points where the blows strike thesheath, and method can be performed in a simple apparathe article, aboutthe axis of the article. tus and notwithstanding this produces a perfect2. The method of welding tubular compound weld, not only on account ofthe uniform action metallic articles of great length, comprising of thedies, or percussion jaws, as against the placing a tubular article on amandrel, placing unequal action of rolls, but also because the dies asheath of welding metal on the article on the breakup any oxide whichmay be present bemandrel, heating the article and the sheath tween thesheath and the article. The metal is thereon to welding'heat, shiftingthe three memnot subjected to tensile stress while hot, and bers axiallyand while still heated striking blows 5o so I am not limited to the useof high tensile in radial' direction, and -in rapid succession, metalsbut may use metals of any mechanical against the sheath, and effectingrelative rotapropertles including those whose tensile strength tion ofthe points where the blows strike the is redu y heating to Welding p uresheath, and the article, about the axis of the In the accompanyingdrawing, I have illusarticle.

trated, by way of example, a machine for making tubular compoundarticles, and a machine for making compound wire.

Fig. 1 shows the formation of a compound tube with the aid ofreciprocating dies, or percussion jaws.

Fig. 2 shows the formation of a compound

